Rihanna

Rihanna

Rihanna's Look-Hot/Feel-Hot Tip: RiRi squeezes in at least three workouts a week while she's on the road, and is also rumored to follow celebrity trainer Harley Pasternak's advice of eating five meals a day that all have the healthy combo of protein, fiber, quality carbs, and fats. That's a surefire recipe for holding on to her bikini bod during any season.

Selena Gomez

Selena Gomez

Her Look-Hot/Feel-Hot Tip: There's lots of pressure on young singers and actresses to have a perfect body (wouldn't you freak out if the paparazzi were taking pictures of you on the beach, especially if you knew it would make front page tabloid news?). Selena has revealed how she learned to not let the pressure get to her: "One of my best friends told me to get up every morning and try to say to yourself, 'I am beautiful,' That helped a lot."